System and approach for water heater comfort and efficiency improvement

ABSTRACT

A system for heating water to improve safety and efficiency. The system may have normal operation measured in time. After a time of normal operation, a water temperature setpoint may be checked. If the setpoint is not at a certain level, normal operation may continue. If the setpoint is within the certain level, water temperature may be measured. If the water temperature is less than a desired level, one or more draws of water may be measured for a preset temperature drop. If the draws do not meet the temperature drop, a return to check the setpoint may be made. If the draws meet the temperature drop, the setpoint may be reduced and a time of normal operation may be measured to determine whether a burn cycle occurs within the time. If not, normal operation may continue; but if so, a return to check the setpoint may be made.

BACKGROUND

The present disclosure pertains to systems designed to heat fluids andparticularly to devices that pertain to the efficiency and safety ofheating fluids.

SUMMARY

The disclosure reveals a system for heating water in a controlled mannerto improve safety and efficiency. The system may have a mode of normaloperation measured in terms of time. After a certain amount of time ofnormal operation, a temperature setpoint of the system may be checked.If the setpoint is not at a certain level, then normal operation maycontinue. If the setpoint is at the certain level, then watertemperature of the system may be measured. If the water temperature isless than a desired level, then one or more draws of water may bechecked for a preset temperature drop. If the draws do not meet thetemperature drop, then a return to the setpoint may be made withsubsequent actions as described herein. If the draws meet thetemperature drop, then the setpoint may be reduced and normal operationmay be measured in terms of time to determine if a burn cycle occurswithin a preset amount of time. If not, then normal operation maycontinue; but if so, a return to a setpoint check may be made along withthe subsequent actions as noted.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a diagram of a water heater that incorporates the presentsystem and approach for heating water;

FIG. 2 is a diagram of an illustrative example of a controller for awater heater;

FIG. 3 is a diagram of a general water heater flow chart; and

FIG. 4 is a diagram of water temperature control of a water heatersystem to prevent generating temperatures of water beyond a certaintemperature to improve safety and energy savings.

DESCRIPTION

The present system and approach may incorporate one or more processors,computers, controllers, user interfaces, wireless and/or wireconnections, and/or the like, in an implementation described and/orshown herein.

This description may provide one or more illustrative and specificexamples or ways of implementing the present system and approach. Theremay be numerous other examples or ways of implementing the system andapproach.

Residential and commercial water heaters may use a ten to fifteen degreedifferential to maintain tank temperature. The temperature control maywork sufficiently to deliver hot water; however, after multiple draws,the water tank can begin to stratify, leading to a set point at 135degrees Fahrenheit (F) producing a temperature near 150 degrees F. atthe top of the tank for supply. The hot water is not necessarily safe orcomfortable for the user and also may waste more energy by increasingthe top of the tank's ambient differential. The present algorithm maylimit the return to a setpoint only during excess demand cycles. Thereduction in return to setpoint may still maintain sufficient hot water;however, the burner advance turnoff could protect the user from scaldingand excess energy consumption.

The burning algorithm may track the gas valve history for the prior fourhours of operation. A counter may track the number of burner on and offand total burner on time of each recovery. In the condition of 2 or moreburn cycles in one hour, the algorithm may go live and on the thirdreheat cycle, the return to setpoint may be limited from zero to tendegrees F., depending on a total prior draw load and total burn timetracked leading up to the 3rd draw with in that hour. The reduction insetpoint may allow the regeneration of heat without the overshoot oftank temperature at the top of the tank. The hot water tank algorithm'sreduction in set point may stay live for up to four hours to allow thetank to equalize tank temp. At that point, the return to set point mayoccur and water temp may rise to the desired tank temp within two tothree degrees F.

FIG. 1 is a diagram of a water heater 30 that may incorporate thepresent system and approach for heating water. A water tank 32 may havean input supply pipe or drip tube 44 for receiving fresh water and anoutput pipe or tube 46 for drawing water, particularly heated water asneeded. Tank 32 may have an inner surface 42 and an outer surface 52.Around tank 32 may be an insulating layer 34 and an external shell 36.In tank 32 may be a rust inhibiting layer 50. Toward a bottom of tank 32may be a drainage valve 48. Water heater 30 and tank 32 may have a topsurface 54. At a bottom of heater 30 and tank 32 at a bottom surface 56may be a heater 38 which can use electricity, gas or a combination tocreate heat for increasing a temperature of water in tank 32. In thediagram of FIG. 1, a gas burner 58 may be used as an illustrativeexample of heater 38. There may be a combustion chamber 63 that issupplied with a fuel such as gas in a tube 66. Combustion chamber 63 mayhave an enclosure 59 and or exhaust pipe flue 66 that runs from chamber63 through tank 32 and top surface 54 to an outside exhaust vent.

An ignition source 40 such as a pilot light may be fed fuel from tube66. A valve 67 may be electrically opened and closed. Valve 67 may closeif not kept warm by pilot 60, particular in the event that the pilot 60is extinguished and cannot light the burner in an event that an electricsignal from a controller 40 is a command to open valve 67. Also, ifpilot 60 goes out, then a thermal valve (a component of valve 67)connected to pilot 60 closes if not kept warm by pilot 60. Theprecautionary measures are for preventing a release of gas from anon-functioning burner 38 and pilot 60.

A sensor 64 may be connected to controller 40 to provide a temperatureof water in tank 32 to controller 40. Input signals 70, sensor signals84 and settings 86 may go to controller 40. Control signals 82 may beprovided by controller 40. Controller 40 may also have controls andindicators for a user. Examples may be gauges, lights, settingselectors, and the like. A controller 40 may be of various versions ofmodels that vary from simple to complex arrangements. Controller 40 mayoperate relative to a program or algorithm as indicated herein.

A diagram in FIG. 2 shows an illustrative example of controller 40.Input signals 70 may go to a processing block 72 which may incorporate aprocessor 71 and memory 78 that are connected to each other. Aconnection line 84 may connect one or more sensors 64 to a sensor inputbuffer circuit 74. Sensor signals may be provided by sensor input buffercircuit 74 to processor 71. Settings 86, such as those of temperatureand time, and the like, may go to settings buffer circuit 80 and then onto processor 71. Output control signals may proceed from processor 71 toalong connection line 82 to one or more valve actuators, and otheractuators or components, and the like. Indicator signals may proceedfrom processor 71 along a connection line 83 to various instruments suchas displays, gauges, indicator lights, sound emanating devices, and thelike. Temperature and other setpoints may be entered along connectionline 86 to a settings buffer circuit 80. From circuit 80, settingsignals may go to processor 71. Entries from inputs may be fromthermostats, keyboards, tunable knobs, switches, and so forth.

FIG. 3 is a diagram of a general water heater flow chart. Symbols mayrepresent blocks, steps, statuses, activity or other items, even thoughthey might be referred to as “symbols” for purposes of the diagram.Symbol 91 may indicate that a water temperature control system is instandby. A question of whether water temperature is less that a setpointminus tolerance may be asked at symbol 92. If an answer is no, thenthere may be a return to standby. If the answer is yes, then a heatingcycle (burn cycle) may occur at symbol 93. At symbol 94, a question ofwhether the water temperature is greater than the setpoint plustolerance may be asked. If an answer is no, then the heating cycle mayoccur. If the answer is yes, then a return to standby may be made.

FIG. 4 is a diagram of water temperature control that may prevent awater heater system from generating temperatures of water beyond acertain temperature to improve safety and energy savings. Symbol 11 mayrepresent normal operation of a water heater. A timer may be started atsymbol 12. A question at symbol 13 may ask whether the timer has run formore than one hour. If an answer is no, then a return may be made tosymbol 11 and symbol 12. The question at symbol 13 may be asked again.If the answer is yes, then a question at symbol 14 may be asked as towhether a set point of the water heater is greater than 125 degreesFahrenheit (F) or less than 150 degrees F. If an answer is no, then areturn may be made to symbol 11 of normal operation. If the answer isyes, then a question at symbol 15 may be asked as to whether a watertemperature in the water heater is less than C*(88 degrees F.). If theanswer is yes, then a return to normal operation at symbol 11 may occur.If the answer is no, then at symbol 16 a question asked may be whethertwo draws within X minutes (60<X<75) with a temperature drop greaterthan D*(˜25 degrees F.) in M (˜10) minutes on each draw. If an answer isno, then a return to symbol 14 may be made with sequences to followsymbol 14 as indicated herein. If the answer is yes, then the set pointmay be reduced by Y*(˜5 to 10 degrees F.) at symbol 17. Subsequently, atimer may be started and normal operation can occur at symbol 18. Aquestion may then be asked at symbol 19 as to whether a burn cycle iswithin four hours. If an answer is no, then a return to normal operationat symbol 11 may occur. If the answer is yes, then a return may be madeto symbol 14 with sequences of operation to follow as indicated herein.

To recap, a water heater control mechanism may incorporate a processorhaving a memory, a temperature sensor situated in a tank of a waterheater and connected to the processor, a heater connected to a valve orswitch, a setpoint device connected to the processor, an actuatorattached to the valve and connected to the processor, and a programsituated in the memory. The processor may have a normal operation forcontrolling temperature of water in the tank relative to a setpoint fortemperature of the water. The program may provide steps that incorporatetiming a length of normal operation, reading the setpoint device if thetiming of a length of the normal operation exceeds a pre-determinedtime, reading the temperature sensor if a reading of the setpoint deviceis between two pre-determined temperatures, measuring one or more drawsin terms of time and temperature if the reading of the temperaturesensor is equal to or greater than a pre-determined temperature,reducing a setting of the setpoint device if the terms of time andtemperature are within pre-defined terms of time and temperature for adraw, timing to when a burn cycle occurs, and reading the setpointdevice if a time until a burn cycle occurs is greater than apre-determined time.

If the reading of the setpoint device is not between the twopre-determined temperatures, then the processor may return to normaloperation.

A return to reading the setpoint device may occur if the terms of timetemperature for a draw are not within the pre-defined terms of time andtemperature for a draw.

If the timing of the length of the normal operation does not exceed thepre-determined time, then the processor may continue in normaloperation.

The two pre-determined temperatures for the setpoint device may bebetween A degrees Fahrenheit and B degrees Fahrenheit.

If the reading of the temperature sensor is equal to or less than thepre-determined temperature, then the processor may return to normaloperation.

The pre-determined temperature for the temperature sensor may be Cdegrees Fahrenheit.

The pre-defined terms of time and temperature may incorporate J draws orK pair or pairs of draws with a period between D minutes and E minuteswith a temperature drop of F degrees Fahrenheit in G minutes on eachdraw.

A return of the processor to normal operation may occur if the timeuntil the burn cycle occurs is equal to or less than the pre-determinedtime.

The pre-determined time for when the burn cycle occurs may be H hours.

Illustrative example numbers for the variables may be A˜125, B˜150,C˜80, D˜60, E˜75, F˜25, G˜10, H˜4, J˜2 and K˜1.

A fluid heater system may incorporate a tank, a heater at the tank, afluid input on the tank, a fluid output on the tank, a heater controldevice connected to the heater, a temperature sensor situated in thetank, a temperature setpoint mechanism, a timer, and a processorconnected to the heater control device, the temperature sensor, thetemperature setpoint mechanism and the timer. The processor may controlthe heater control device, adjust the temperature setpoint mechanism andoperate a timer in response to the temperature sensor, according to aprogram.

A maximum temperature of a fluid in the tank may be controlled by theprocessor and heater control device according to the program.

A setpoint on temperature setpoint mechanism may result in a temperatureof a fluid in the tank greater than a temperature indicated by thesetpoint due to temperature stratification of the fluid in the tank. Theprogram may limit a return to a setpoint just during excess demandcycles, to reduce the temperature of the fluid in the tank increased bytemperature stratification.

The heater may be a gas burner. The heater control device mayincorporate a valve connected to the gas burner, and an actuator thatcontrols the valve and is connected to the processor. The program maytrack a history of the valve that reveals a number of times that aburner turns on and off and the total on-time of the burner. After asequence of a pre-determined number of times that the burner turns onand off, the program may limit a return to the setpoint by a certainnumber of degrees less than the setpoint of the temperature setpointmechanism according to the total on-time of the burner and amount offluid draw from the tank within a given period of time.

The heater may be electric.

Steps of the program may incorporate 1) measuring a time of a normaloperation of the processor, 2) checking a setpoint of the temperaturesetpoint mechanism if a time of the normal operation exceeds an A hourduration, 3) detecting a temperature less than B degrees Fahrenheit ofthe fluid if the setpoint of the temperature setpoint mechanism isbetween C degrees and D degrees Fahrenheit to take the processor out ofnormal operation, 4) making E draws of fluid from the tank within an Fminute duration between a G minute duration and an H minute durationwith a temperature drop detected by the temperature sensor greater thanI degrees Fahrenheit of a J minute duration on each draw occurring thatresults in reducing the setpoint by K degrees between L degrees and Mdegrees, or in absence of each draw occurring as such results in goingto step 3), 5) measuring a time of another normal operation of theprocessor, and 6) determining that an electric heat cycle has occurredwithin an N hour duration and thus resulting in returning to step iii),or determining that an electric heat cycle has not occurred thusresulting in the processor remaining in normal operation.

A, B, C, D, E, F, G, H, I, J, K, L, M, and N may be numbers associatedwith units as fitting in their context.

One or more items may be selected from a group incorporating A beingabout 1, B being about 80, C being about 125, D being about 150, E beingabout 2, F being between G and H, G being about 60, H being about 75, Ibeing about 25, J being about 10, K being between L and M, L being about5, M being about 10, and N being about 4.

One or more items may be selected from a group comprising A is between0.05 and 5, B is between 40 and 120, C is 80, D is 200, E is between 1and 10, F is between G and H, G is 5, H is 250, I is between 5 and 125,J is between 1 and 60, K is between L and M, L is 0, M is 50, and N isbetween 0.1 and 10.

A water heater may incorporate a tank, a water heater attached to thetank, a control device connected to the water heater, a temperaturesensor in the tank, a temperature setpoint mechanism, and a controllerconnected to the control device, temperature sensor and a temperaturesetpoint mechanism. The processor may operate according to a programthat causes normal operation of the heater to be overridden by anoccasional setpoint adjustment to ensure efficiency and a supply safehot water temperature.

The program may incorporate occasionally checking the setpoint of thetemperature setpoint mechanism, continuing normal operation if thesetpoint is at an acceptable setting, obtaining a temperature of waterin the tank from the temperature sensor if the setpoint is absent from apredetermined setting, returning to normal operation if the temperatureof the water is at predetermined magnitude, obtaining a temperature dropevaluation of one or more draws of water if the temperature of the wateris absent from a predetermined magnitude, rechecking the setpoint if thetemperature drop evaluation is high, reducing the setpoint if thetemperature drop evaluation is low, starting timing normal operation ofthe heater to detect whether a burn cycle occurs within a predeterminedperiod of time, rechecking the setpoint if the burn cycle occurs, andcontinuing normal operation if a burn cycle does not occur.

U.S. patent application Ser. No. 14/225,308, filed on Mar. 25, 2014, ishereby incorporated by reference.

Any publication or patent document noted herein is hereby incorporatedby reference to the same extent as if each individual publication orpatent document was specifically and individually indicated to beincorporated by reference.

In the present specification, some of the matter may be of ahypothetical or prophetic nature although stated in another manner ortense.

Although the present system and/or approach has been described withrespect to at least one illustrative example, many variations andmodifications will become apparent to those skilled in the art uponreading the specification. It is therefore the intention that theappended claims be interpreted as broadly as possible in view of therelated art to include all such variations and modifications.

What is claimed is:
 1. A water heater control mechanism comprising: aprocessor having a memory; a temperature sensor situated in a tank of awater heater, and connected to the processor; a heater connected to avalve or switch; a setpoint device connected to the processor; anactuator attached to the valve and connected to the processor; and aprogram situated in the memory; and wherein: the processor has a normaloperation for controlling temperature of water in the tank relative to asetpoint for temperature of the water; the program provides steps thatcomprise: timing a length of normal operation; reading the setpointdevice if the timing of a length of the normal operation exceeds apre-determined time; reading the temperature sensor if a reading of thesetpoint device is between two pre-determined temperatures; measuringone or more draws in terms of time and temperature if the reading of thetemperature sensor is equal to or greater than a pre-determinedtemperature; reducing a setting of the setpoint device if the terms oftime and temperature are within pre-defined terms of time andtemperature for as a draw; timing to when a burn cycle occurs; andreading the setpoint device if a time until a burn cycle occurs isgreater than a pre-determined time.
 2. The mechanism of claim 1, whereinif the reading of the setpoint device is not between the twopre-determined temperatures, then the processor returns to normaloperation.
 3. The mechanism of claim 1, wherein a return to reading thesetpoint device occurs if the terms of time temperature for a draw arenot within the pre-defined terms of time and temperature for a draw. 4.The mechanism of claim 1, wherein if the timing of the length of thenormal operation does not exceed the pre-determined time, then theprocessor continues in normal operation.
 5. The mechanism of claim 2,wherein the two pre-determined temperatures for the setpoint device arebetween A degrees Fahrenheit and B degrees Fahrenheit.
 6. The mechanismof claim 1, wherein if the reading of the temperature sensor is equal toor less than the pre-determined temperature, then the processor returnsto normal operation.
 7. The mechanism of claim 2, wherein thepre-determined temperature for the temperature sensor is C degreesFahrenheit.
 8. The mechanism of claim 3, wherein the pre-defined termsof time and temperature comprise J draws with a period between D minutesand E minutes between the draws with a temperature drop of F degreesFahrenheit in G minutes on each draw.
 9. The mechanism of claim 1,wherein a return of the processor to normal operation if the time untilthe burn cycle occurs is equal to or less than the pre-determined time.10. The mechanism of claim 9, wherein the pre-determined time for whenthe burn cycle occurs is H hours.
 11. A fluid heater system comprising:a tank; a heater at the tank; a fluid input on the tank; a fluid outputon the tank; a heater control device connected to the heater; atemperature sensor situated in the tank; a temperature setpointmechanism; a timer; and a processor connected to the heater controldevice, the temperature sensor, the temperature setpoint mechanism andthe timer; and wherein the processor controls the heater control device,adjusts the temperature setpoint mechanism and operates a timer inresponse to the temperature sensor, according to a program.
 12. Thesystem of claim 11, wherein a maximum temperature of a fluid in the tankis controlled by the processor and heater control device according tothe program.
 13. The system of claim 11, wherein: a setpoint ontemperature setpoint mechanism can result in a temperature of a fluid inthe tank greater than a temperature indicated by the setpoint due totemperature stratification of the fluid in the tank; and the programlimits a return to a setpoint just during excess demand cycles, toreduce the temperature of the fluid in the tank increased by temperaturestratification.
 14. The system of claim 11, wherein: the heater is a gasburner; the heater control device comprises a valve connected to the gasburner and an actuator that controls the valve and is connected to theprocessor; the program tracks a history of the valve that reveals anumber of times that a burner turns on and off and the total on-time ofthe burner; and after a sequence of a pre-determined number of timesthat the burner turns on and off, the program limits a return to thesetpoint by a certain number of degrees less than the setpoint of thetemperature setpoint mechanism according to the total on-time of theburner and amount of fluid draw from the tank within a given period oftime.
 15. The system of claim 11, wherein the heater is electric. 16.The system of claim 11, wherein steps of the program comprise: i)measuring a time of a normal operation of the processor; ii) checking asetpoint of the temperature setpoint mechanism if a time of the normaloperation exceeds an A minute duration; iii) detecting a temperatureless than B degrees Fahrenheit of the fluid if the setpoint of thetemperature setpoint mechanism is between C degrees Fahrenheit and Ddegrees Fahrenheit to take the processor out of normal operation; iv)making E draws of fluid from the tank within an F minute durationbetween a G minute duration and an H minute duration with a temperaturedrop detected by the temperature sensor greater than I degreesFahrenheit of a J minute duration on each draw occurring then results inreducing the setpoint by K degrees Fahrenheit between L degreesFahrenheit and M degrees Fahrenheit, or in absence of each drawoccurring as such results in going to step iii); v) measuring a time ofanother normal operation of the processor; and vi) determining that anelectric heat cycle has occurred within an N minute duration and thusresulting in returning to step iii), or determining that an electricheat cycle has not occurred thus resulting in the processor remaining innormal operation.
 17. The system of claim 16, wherein A, B, C, D, E, F,G, H, I, J, K, L, M and N are numbers having units as fitting in theirrespective contexts.
 18. The system of claim 17, wherein one or moreitems can be selected from a group comprising A is between 5 and 300, Bis between 40 and 120, C is 80, D is 200, E is between 1 and 10, F isbetween G and H, G is 5, H is 250, I is between 5 and 125, J is between1 and 60, K is between L and M, L is 0, M is 50, and N is between 10 and600.
 19. A water heater comprising: a tank; a water heater attached tothe tank; a control device connected to the water heater; a temperaturesensor in the tank; a temperature setpoint mechanism; and a controllerconnected to the control device, temperature sensor and a temperaturesetpoint mechanism; and wherein the processor operates according to aprogram that causes normal operation of the heater to be overridden byan occasional setpoint adjustment to ensure efficiency and a supply safehot water temperature.
 20. The heater of claim 19, wherein the programcomprises: checking the setpoint of the temperature setpoint mechanism;continuing normal operation if the setpoint is at an acceptable setting;obtaining a temperature of water in the tank from the temperature sensorif the setpoint is not at a predetermined setting; returning to normaloperation if the temperature of the water is at predetermined magnitude;obtaining a temperature drop evaluation of one or more draws of water ifthe temperature of the water is not at a predetermined magnitude;rechecking to the setpoint if the temperature drop evaluation is high;reducing the setpoint if the temperature drop evaluation is low;starting timing normal operation of the heater to detect whether a burncycle occurs within a predetermined period of time; rechecking thesetpoint if the burn cycle occurs; and continuing normal operation if aburn cycle does not occur.